Fix reline on OpenBSD

OpenBSD doesn't support tiparm, only tparm.  I'm not sure if the
two are compatible, but this at least this allows me to run irb
on OpenBSD.

lib/reline/terminfo.rb

@@ -40,7 +40,12 @@ module Reline::Terminfo
   #extern 'char *tigetstr(char *capname)'
   @tigetstr = Fiddle::Function.new(curses_dl['tigetstr'], [Fiddle::TYPE_VOIDP], Fiddle::TYPE_VOIDP)
   #extern 'char *tiparm(const char *str, ...)'
-  @tiparm = Fiddle::Function.new(curses_dl['tiparm'], [Fiddle::TYPE_VOIDP, Fiddle::TYPE_VARIADIC], Fiddle::TYPE_VOIDP)
+  @tiparm = begin
+    Fiddle::Function.new(curses_dl['tiparm'], [Fiddle::TYPE_VOIDP, Fiddle::TYPE_VARIADIC], Fiddle::TYPE_VOIDP)
+  rescue
+    # OpenBSD lacks tiparm
+    Fiddle::Function.new(curses_dl['tparm'], [Fiddle::TYPE_VOIDP, Fiddle::TYPE_VARIADIC], Fiddle::TYPE_VOIDP)
+  end
   # TODO: add int tigetflag(char *capname) and int tigetnum(char *capname)
 
   def self.setupterm(term, fildes)